Inputting in Chrome URL Bar Triggering UI Freeze, pegged CPU and Major Memory Leak

[Victorzwl]

OS: Ubuntu 17.10 (Linux weilong-Ubuntu 4.13.0-16-generic #19-Ubuntu SMP Wed Oct 11 18:35:14 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux)

GNOME version: GNOME Shell 3.26.1
Chrome version: Version 62.0.3202.75 (Official Build) (64-bit)

Description:

This may very likely have something to do with my Chinese input method (iBus). I encounter this consistently while the system input method is Chinese (WubiHaifeng86) but the mode within the input method is English.

Inputting in Chrome URL bar is triggering UI freeze and major memory meak. The whole UI freezes and won't respond to either mouse or keyboard. Can't switch to console by Ctrl+Alt+Fx. Was able to ssh in from another machine and gather information.

Reproduce Steps:

1. Switch system input method to Chinese (WubiHaifeng86)
2. Switch to English inputting mode (while system input method is still Chinese).
3. Open Chrome
4. Input some characters in URL bar and the bug should occur. If not, use Backspace to delete some and input some more.

(Sometimes swapping step 2 and 3 might help reproduce the issue.)

Some info:

top:

top - 11:35:02 up 23 min, 3 users, load average: 2.70, 2.10, 1.20
Tasks: 221 total, 4 running, 217 sleeping, 0 stopped, 0 zombie
%Cpu(s): 59.1 us, 2.9 sy, 0.0 ni, 37.9 id, 0.0 wa, 0.0 hi, 0.1 si, 0.0 st
KiB Mem : 8161428 total, 1386928 free, 5591952 used, 1182548 buff/cache
KiB Swap: 472404 total, 472404 free, 0 used. 2244372 avail Mem

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
  870 weilong 20 0 7634048 3.726g 100292 R 116.9 47.9 6:50.39 gnome-shell
 1376 weilong 20 0 399472 40320 8032 R 91.0 0.5 4:19.32 ibus-daemon
 1591 weilong 20 0 273556 32908 14976 S 26.2 0.4 1:18.30 python3
 1805 weilong 20 0 1513112 260204 119888 S 10.6 3.2 1:35.11 chrome
  256 root 20 0 88024 13660 12756 S 1.3 0.2 0:05.23 systemd-journal
  922 weilong 20 0 732384 66480 53788 S 1.3 0.8 0:21.74 Xwayland
 2211 weilong 20 0 1316096 169220 58552 S 1.0 2.1 0:13.77 chrome
 2078 weilong 20 0 1164120 99948 59080 S 0.7 1.2 0:06.08 chrome
   35 root 20 0 0 0 0 S 0.3 0.0 0:02.60 kworker/2:1

syslogs:

Oct 29 12:58:59 weilong-Ubuntu google-chrome.desktop[10633]: Created new window in existing browser session.
Oct 29 12:59:21 weilong-Ubuntu org.gnome.Shell.desktop[5354]: Key repeat discarded, Wayland compositor doesn't seem to be processing events fast enough!
Oct 29 12:59:24 weilong-Ubuntu org.gnome.Shell.desktop[5354]: message repeated 105 times: [ Key repeat discarded, Wayland compositor doesn't seem to be processing events fast enough!]
Oct 29 12:59:24 weilong-Ubuntu org.gnome.Shell.desktop[5354]: Key repeat discarded, Wayland compositor doesn't seem to be processing events fast enough!
^C

This bug is also reported to https://bugzilla.gnome.org/show_bug.cgi?id=789634

A screenshot seconds before the issue occurs is attached. Notice at the right top corner, the system input method is Chinese but in English inputting mode (showing a "英" character to indicate English inputting mode with Chinese Input method selected)

ProblemType: Bug
DistroRelease: Ubuntu 17.10
Package: gnome-shell 3.26.1-0ubuntu5
ProcVersionSignature: Ubuntu 4.13.0-16.19-generic 4.13.4
Uname: Linux 4.13.0-16-generic x86_64
ApportVersion: 2.20.7-0ubuntu3.1
Architecture: amd64
CurrentDesktop: ubuntu:GNOME
Date: Sun Oct 29 14:45:33 2017
DisplayManager: gdm3
GsettingsChanges:
 b'org.gnome.shell' b'command-history' b"['ubuntu-bug gnome', 'ubuntu-bug gnome-shell']"
 b'org.gnome.shell' b'app-picker-view' b'uint32 1'
 b'org.gnome.shell' b'favorite-apps' b"['firefox.desktop', 'rhythmbox.desktop', 'org.gnome.Nautilus.desktop', 'org.gnome.Software.desktop', 'yelp.desktop', 'google-chrome.desktop', 'org.gnome.Terminal.desktop', 'sublime_text.desktop']"
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'ibus'"
InstallationDate: Installed on 2017-10-29 (0 days ago)
InstallationMedia: Ubuntu 17.10 "Artful Aardvark" - Release amd64 (20171018)
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Daniel van Vugt (vanvugt)]

Thank you for reporting this bug to Ubuntu.
Ubuntu 17.10 (artful) reached end-of-life on July 19, 2018.

See this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test. If you then find the bug is still present in the newer Ubuntu version, please add a comment here telling us which new version it is in and change the bug status to Confirmed.